I have two that on occasion will seek out a spot under the bed or in the back of my closet. With mine I do believe it is indicative that something is not right with them. Tucker did it when he first came to live with us and then lately when he has had his mini seizures. Hannah will do it in spurts, do it for several days at a time and then not for a long time. I had a guest dog here who also sought solice under the bed. My conclusion based on my own dogs is that it is in a way indicating that something is just not right for them - may be very minor or may be a medical problem.